Door closing mechanism



Dec. 5, 1961 Filed March 6, 1959 H. BOMM El'AI.

DOOR CLOSING MECHANISM 2 Sheets-Sheet 1 l2 FIG.

, I 58 a 2| i 26 57 55 l7 INVENTORS HEINZ BOMM 8: KLAU S BE R GHAU PATENT AGENT The present invention relates to an improved door closing device operating from the top of a door and being provided with a hydraulic brake or dashpot.

The instant door closer is of the type comprising a unitary housing adapted to be secured to the top portion of a door frame, an inner casing'supported by said unitaryhousing accommodating a spiral spring circumferentially disposed about a spindle, and a dashpot assembly including a piston and a connecting rod interconnecting said spindle with said piston. The spindle, in turn, is secured to lever means which are fastened to the header of a door frame. A rotating eccentric portion is provided on the free end of the spindle, the connecting rod for the piston of the dashpot being rotatably mounted on this eccentric portion.

In order to obtain the necessary return force for closing a door, door closing mechanisms operating from the upper edge of a door require a certain minimum height which is dependent on the width of the spring disposed in the spring casingu In the instant case, a ratchet means is employed in order to tension the spiral spring, said ratchet means being connected to a door-frameconnecting lever, whereas the end of the spring engages in a locking slot provided in the spring casing. The

ratchet wheel can be rotated relative to the spindle inorderto adjust the biasing force of the'spiral spring.

' Door closing devices of the type operating from the top are relatively foolproof and require very-little maintenance. I However, such top door closers have the disadvantage that they are relatively bulky, particularly with respect to their height and, additionally, they are ratherconspicuous and often unattractive. The latter disadvantages are overcome by employing bottom door closers. However, the convenient assemblage, the ready adjustability, the foolproofness in operation and the slight maintenance required of a top door closing device distinguishes the latter favorably from the bottom doorcloser, so that top door closers will maintain their marketability.

"It is, therefore, an important object of the-present invention to provide a door closer which is relatively simple in construction and yet highly reliable in operation. 4

It is another object of the presentinvention to pro' vide a. door closerwhich is compact and attractive in It is another object of the invention to provide means enabling the horizontal center plane of a dashpot cylinderappearance and wherein the structural height of the casingis decreased.

to be displaced in order to reduce the required heightof' the housing. i i It is another important feature of the invention to pro-- vide means for additionally journalling the spindle to ensure greater reliability in operation of the door closing mechanism. i f It is a further object of the invention to provide m'e'ans enabling the width of a spiral return spring to be decreased and, correspondingly, to increase the thickness 'or strength of a spring band.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be underee wn examples, while indicating invention, are given by way of illustration only, since stood, however, that the detailed description andspecific various changes and modifications within the spirit and scope of the invention will become apparent to those.

skilled in the art from this detailed description.

In the drawings:

FIGURE 1 discloses a longitudinal'section'of the door closing mechanism according to the present invention;

FIGURE 2 illustrates a top view of the device with' the top portion or lid removed;

FIGURE 3 shows in detail the structure of the piston and connecting rod for the dashpot;

FIGURE 4 illustrates in detail the structure of the ratchet wheel for pretensioning a spring member;

' FIGURE 5 shows a front view of a mounting plate employed with the door closing mechanism;

' FIGURE 6 is a side view of the mounting plate shown 7 in FIGURE 5;

FIGURE 7 is a sectional'view of the mounting plate shown in FIGURE 5 taken along the line AA, with the door closing assembly mounted on a metal door having a narrow door frame partially shown in section;

' FIGURE 8 is a fragmentary sectional view of the door closer housing and its associated mounting plate;

FIGURE 9 illustrates a top view of the door closing assembly-according to the invention, the top portion of the housing being partially cut open. I

Referring in detail to the drawings and, more particulary, to FIGURES l and. 4, the door closingassembly according to the present invention comprises a unitary external housing 24. Within said external housing 24,

there is provided an inner casing for housing a spring S ,v

said spring being narrower and stronger than heretofore used, and a brake piston 17, which will be more fully explained hereinafter. A bushing 2 is centrally 'disposed within a cylindrical spring casing 1, said bushing having lateral shoulders50 which securely bear. against the inner stepped recess 51 provided in the floor of the spring casing 1. A rotatable spindle 4, having its axis parallel to the hinge of the door, is coaxially mounted within the bushing 2 and has one end additionally jour-,

spring 9 disposed in said spring casing 1. The upper portion of the spindle 4 carries a threaded; keyway10 to which is secured a connecting lever 11 by means of a threaded bolt 10a. The head of the lever 11 is provided with a hollow channel 53 supporting a stub shaft 54 onto which a detent element 12 is pivotally mounted,

said detent' element engaging the slots 13 of theratchet wheel6, whereby rotation of, the ratchet wheel and subsequent engagement of the detent member with one of the'slots 13 effects a predetermined pretensioning of the spiral spring 9. As a result of this arrangement, a coupling pin or bolt, normally provided on the ratchet wheel 6, is no longer necessary, whereby the height" of the head' of the connecting lever 11 can be decreased by the height of the ratchet means associated therewith. The connecting lever 11 is secured to the header of a door" frame (not shown) in a "conventional manner, whereas the external housing 24 is mounted on the top of the-door by means of the lateral flange members-14 and 15. I

The dashpot assembly includes a cylinder 16, disposed both below' andlaterally with respect'to the spring casing 1, and a piston 17 arranged for reciprocating movement withinsaidicylinder 16. A connecting element or rod 18'. has" one end connected to the piston. 17 by means Patented Dec. 5, 19st preferred embodiments of the I of a pin 55 fitted into the head of said piston at approximately the central portion thereof. The opposite end of said connecting rod 18 is inclined downwardly and is, formed as a bearing portion or journal 20 which encompasses a circular but eccentrically arranged portion 19 at the lower end of the spindle 4.

Thus, it will be apparent that the horizontal center line of the dashpot cylinder and the eccentric portion 19, V

respectively, are lying in different planes, i.e., that due tothe fact that the elongated intermediate portion of the connecting element 18 is inclined relative to the axis. about whichthe spindle 4 rotates, the end of the element 18 which is attached to the piston 17 lies in aplane that. is normal to this axis, which last-mentioned plane is spaced a substantial distance from the. other end of the element, namely, the end which isformed as the bearing portion 20 that encompasses .the eccentric portion 19 of the spindle 4. As a result of this arrangement, the height of the door closing mechanism is substantially decreased without increasing the side dimension necessary for the braking mechanism. This holds true irrespective of whether hydraulic or mechanical means are employed for the dashpot mechanism as the.

pressure means is controlled in response to the rotation of the spindle 4. Thus, in accordance with the invention, it is possible to displace the horizontal center plane of the piston 17 and dashpot cylinder 16 a distance corresponding to the height. the connecting rod 18 is upwardly inclined, whereby the structural height of the de-.

vice is decreased by at least one-half the diameter of the cylinder 16,. without impairing the function of the structure. provided laterally of the spring housing, no increase in the diameter ofthe external. housing is necessary.

It,will also be noted that the spring casingl is so formed that the chamber within which the ,s'pring 9. is received is very deep so that at least partofthe damp-.- ing cylinder 16 ,lies in a plane whichisnormal to the; axis. of;the spindle, 4 and which passes, through the.

spring. 9.

The piston .17 is provided with a check valvemechanisrn 56 .of conventional design permittinginflux ,offla, hydraulic medium into thedashpot cylinder .16 tocushion, In addition, fluid bypass passageways 57, and a control valve 58 are-pro the return movement of the door.

vided which areconventional in the art and, therefore,

need not .be. described. The control-valve 58;;regulates; therate ofefflux of the fluid mediumby means of the,

bypass to ensure effective braking of the door.

The wall of the spring casing 1 is cut away at its rear and front portions to define. abutments 21-against whichthe. outer end 22 of the. spiralrspring 9 is bearingduring rotation thereof, said spring being held together by means of a steel clip or band 23. The internal hous ing is disposed within the external housing,24-and pro-J vided with a cover or lid 25 serving to closethe rear. face of this external housing. As a result of-the up-,.

ward displacement of the dashpot cylinder 16, the-left flange 14 adjacent this. dashpot cylinder 16 had to be narrowedin height; and, therefore, is made so .wide that it can receive two mountingbores 26 arranged ad-. jacen-tv one another. As the. dashpot isonly-on the-left side of the mechanism, see FIGURE 1, the right flange 15 can be provided with ,two mounting bores 26; ar-, ranged underneath one another. It will. be apparentthat, according to thepresent invention, ,a'sp ace saving and compact arrangement is obtained which is especially well suitedfor use with metal doors ,having narrow door frames. Asa result thereof,' intermediatmmembers; usually employed for mounting conventional door closers, can. be omitted. 1

FIGURES m7 vof the-drawings show amounting plate ,27 to which is secured the inventivedoor-closing assembly by meansmfv mounting members 1 28., The mountingplate 27 is attached to-ametalframefilzofa Since. the dashpotcylinder'has always been door by means of fastening bolts 29 extending through suitable apertures 30 provided in the mounting plate 27 and through spacer elements 31. Brackets or flap members 33 are cut into and flexed at approximately right angles to the mounting plate 27 "and spaced above and below the mounting member 28.. Each top flap 33 is provided with a threadedaperture 35, whereas. each lowerflap hasa plainbore 34 aligned with said threaded aperture 35. Inassembling the device, the mounting members '28 are inserted between the flexed brackets 33. As a result of thisarrangement, the door closer will be suspended between said brackets 33, so that a mechanic, during installation of the device, has his hands free to perform other functions and, moreover, is not required A primary advantage of the novel mounting resides in. the possibilityof assembling the unit in the shop and of mounting the door closer by a single person. The rear, of the mounting plate 27 may be designed so that it can be either partially or entirely inserted in the, groove of the metal door frame.

A plurality of flaps 38 are cut from the longitudinalsides of the mounting plate 27 and are bent outwardly at a slight inclination, i.e., about 30. The cup-shaped ex-' ternal housing 24 isprovided on its inner walls, adjacent its-edges, with stop elements or protrusions 39 adapted to grip over the outer edges of the flaps 38 to ensure that the housing 24 will be securely held onto the mount ing plate 27.

According to. FIGURE 8, the mounting plate 27 is provided on its edges with flanges 59 which are forwardly bent portions of this plate and are adapted to hold there-- on the housing 24 with a press fit.

It is possible to make the mounting plate 27 of thinner sheet material and to. secure thereto separate angle mem-. bers serving as flaps 33. These angle members may then be provided with bores adapted to receive bolts serving as supporting means for both the door closing assembly and the mounting plate.

In accordance with FIGURES 7 and 9, the outer h0using'24 is provided with a cutout 40 in the zone of the pivot axis of the connecting lever 11, said cutout permitting assembly of the outer housing 24 to the mounting plate 27. Th'eprovision of this cutout 40, extending to the mounting plate 27, however, makes it possible for dust I and other foreign matter to penetrate the housing 24. To overcome this disadvantage, a cover sheet 41 is provided around the spindle 4 between the spring casing 1 and the ratchet wheel 6. The outer housing is then placed over this cover sheet 41 to obtain a tight door closer assembly. The cover sheet or plate 41 is provided with a lug 42 which abuts one face of the mounting plate 27'to tightly close the cutout40 when the housing 24 is assembled thereover. In order to prevent turning of the cover sheet 41, a boss or protuberance 43 is provided on the lug 42,. so that the edge of said boss 43 bears against the edge 44 of the cutout 40. The housing 24 has a smooth outer surface which can be easily cleaned.

The operation of the door closing mechanism is as follows: Initially, the ratchet wheel 6 is rotated to a desired position'and the detent 12 is gravitated into one of the :peripheral slots .13.in:order to pre-tension the spiral spring 9. Upon opening of the door, the lever 11 rotates the spindle4 and theratchet wheel 6, the latter tensioning the spring .9 to-storeielastic energy for closing the door. Therotation of the spindle 4 causes displacement of the piston-17 to the; right and, simultaneously, causes admittance of a fluid medium through the check valve 56 into the dashpot cylinder. During closing of the door, the spring 9 releases its stored energy and the fluid medium is bypassed and returned to the hydraulic system, acting as a cushion for the door, so as not to slam shut unduly rapidly. It will, thus, be apparent that the instant invention encompasses a novel door closing mechanism which is reliable in its operation and more compact than the devices of this kind heretofore known.

We claim:

1. In a door closer, the combination which comprises: a housing; a spindle mounted in said housing for rotation about an axis, said spindle having near one end an eccentric portion; spring means encompassing said spindle; and damping means arranged in said housing, said damping means comprising a cylinder at least part of which lies in a plane which is normal to said axis and which passes through said spring means and the axis of which cylinder intersects said spindle axis at a point between said eccentric portion and the other end of said spindle, said damping means further comprising a piston slidably arranged in said cylinder and a connecting element one end of which is attached to said piston at approximately the ceritral portion thereof and the other end of which element is formed as a bearing portion and encompasses said eccentric portion of said spindle, said element having an elongated intermediate portion which is inclined relative to said spindle axis so that said one end of said element which is attached to said piston lies in a plane normal to said spindle axis which last-mentioned plane is spaced a substantial distance from said other end of said element which is formed as said bearing portion and encompasses said eccentric portion of said spindle.

2. The combination defined in claim 1, further comprising wall means encompassing said-spindle and forming an annular chamber within which said spring means are arranged, said eccentric portion of said spindle being arranged immediately below the bottom of said chamber.

3. The combination defined in claim 2, wherein said wall means are formed with a plurality of radial cutouts which divide said wall means into a plurality of wall portions.

4. The combination defined in claim 3, wherein said spring means are spiral and have an outer end portion hooked to an edge ofone of said wall portions, whereby said spring means may be so hooked as to impart clockwise or counter-clockwise rotation to said spindle.

5. The combination defined in claim 1 wherein said housing comprises a cap-like member and a mounting plate serving to mount said housing onto a support and covering the opening of said cap-like member, thereby enclosing the other components of the door closer.

6. The combination defined in claim 5, wherein said mounting plate is provided with a plurality of inwardly bent. ear portions, wherein said housing has at least one mounting member adapted to fit between two of said inwardly bent ear portions of said mounting plate, and wherein said mounting member and said ear portions are joined together by a releasable bolt member extending in a direction generally parallel to said spindle axis.

7. The combination defined in claim 5, wherein said cap-like member is provided with a cut-out through which said other end of said spindle projects, and wherein there is provided a cover sheet for covering said cutout.

References Cited in the file of this patent UNITED STATES PATENTS 1,339,479 Schmidt May 11, 1920 1,996,117 Moore Apr. 2, 1935 2,271,098 Schmidt Jan. 27, 1942 2,673,367 Ferguson 1 Mar. 30, 1954 2,723,416 Schlage Nov. 15, 1955 2,885,721 Lipschutz May 12, 1959 FOREIGN PATENTS 552,570 Canada Feb. 4, 1958 

